Add a new determinism test

This is one of the testcases that I forgot to commit

testsuite/driver/extra_files.py

@@ -202,6 +202,7 @@ extra_src_files = {
   'determ017': ['A.hs'],
   'determ018': ['A.hs'],
   'determ019': ['A.hs'],
+  'determ021': ['A.hs'],
   'dodgy': ['DodgyA.hs'],
   'driver011': ['A011.hs'],
   'driver012': ['A012.hs'],

testsuite/tests/determinism/determ021/A.hs

+{-# LANGUAGE ApplicativeDo #-}
+{-# OPTIONS_GHC -ddump-types #-}
+module A where
+
+test2 f = do
+  x <- f 3
+  y <- f 4
+  return (x + y)

testsuite/tests/determinism/determ021/Makefile

+TOP=../../..
+include $(TOP)/mk/boilerplate.mk
+include $(TOP)/mk/test.mk
+
+determ021:
+	$(RM) A.hi A.o
+	'$(TEST_HC)' $(TEST_HC_OPTS) -O -dinitial-unique=0 -dunique-increment=1 A.hs
+	$(CP) A.hi A.normal.hi
+	$(RM) A.hi A.o
+	'$(TEST_HC)' $(TEST_HC_OPTS) -O -dinitial-unique=16777215 -dunique-increment=-1 A.hs
+	diff A.hi A.normal.hi

testsuite/tests/determinism/determ021/all.T

+test('determ021',
+     extra_clean(['A.o', 'A.hi', 'A.normal.hi']),
+     run_command,
+     ['$MAKE -s --no-print-directory determ021'])

testsuite/tests/determinism/determ021/determ021.stdout

+[1 of 1] Compiling A                ( A.hs, A.o )
+TYPE SIGNATURES
+  test2 ::
+    forall t b (f :: * -> *).
+    (Num b, Num t, Applicative f) =>
+    (t -> f b) -> f b
+TYPE CONSTRUCTORS
+COERCION AXIOMS
+Dependent modules: []
+Dependent packages: [base-4.9.0.0, ghc-prim-0.5.0.0,
+                     integer-gmp-1.0.0.1]
+[1 of 1] Compiling A                ( A.hs, A.o )
+TYPE SIGNATURES
+  test2 ::
+    forall t b (f :: * -> *).
+    (Num b, Num t, Applicative f) =>
+    (t -> f b) -> f b
+TYPE CONSTRUCTORS
+COERCION AXIOMS
+Dependent modules: []
+Dependent packages: [base-4.9.0.0, ghc-prim-0.5.0.0,
+                     integer-gmp-1.0.0.1]